IEEE International Superconductive Electronics Conference (ISEC)

Noise Contribution to Switching Current Distributions in NbN Nanowires

Qu Ashley, Di Zhu, Karl K. Berggren

Published Jul 1, 2019• 0 citations

Abstract

The working mechanism behind superconducting nanowire-based devices is the electrothermal transition from the superconducting to normal state, at which the point is known as the switching current. Due to the stochastic nature of nanowires from thermal fluctuations, quantum fluctuations, electrical noise, and black-body radiation, superconducting nanowire-based devices suffer from low repeatability in measurements. Here, we use a tapered and non-tapered NbN nanowire to identify and quantify the effects of ramp rate on the switching current distribution at 1 K. We also plan to expand the model presented by McCaughan et al that includes the noise of the measurement system.

DOI: 10.1109/isec46533.2019.8990925

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